Synergistic fungicidal compositions



K ZEILE ET AL SYNERGISTIC FUNGICIDAI.. COMPOSITIONS Filed July 19, 1960 %.LO3:;|3 'IVGIOISNnd April 17, 1962 ATTORNEYS v 3,030,253 Patented Apr. 17, 1962 3,030,263l SYNERGISTIC FUNGICIDAL COMPOSITIONS Karl Zeile, Richard Sebring, and Peter Schicke, Ingelheim, Germany, assignors to C. H. Boehringer Sohn, Ingelheim (Rhine), Germany, a limited partnership Filed July 19, 1960, Ser. No. 43,815 f I Claims priority, application Germany July 23, 1959 i' i 4 Claims. (Cl. 167-14) This invention relates to fungicidal compositions and,

more particularly to fungicidal compositions containing dithiocarbamic acid salts and calcium polysuldes as active ingredients.

It is known that thiocarbamates have excellent fungicidal properties and are useful in combatting numerous phytopathogenic fungi.

{ Uite, States Patent "Obfice However, they are not effective).

against true mildew fungi (Erysiphaceae family). It is further known that calcium polysulides are useful in combatting plant diseases caused by fungi, but they are primarily effective against true mildew fungi. lt' is also known .to use barium polysulfde to combat fungi. A

combination of barium .polysulde with tetramethylthiuram-disulde is not possible, as indicated in the Plant Protection Summary of Bayer, page 48. ,v

Thiocarbamates are generally relatively'expensive compounds, but they exhibit a good plant compatibility. Inr

contrast, thereto, calcium polysuldes Jare' substantially cheaper, but they readilyV lead to undesirable damageto the plants in higher concentrations.

We have now surprisinglyfound that Ya mixture containingra thiocarbarnate .and acalciumpolysuliide exhibits a considerable synergistic effect with respect to the fungicidal activity.

In other words, the fungicidal activity of such a composition far exceeds the expected additive effect of the individual components.

Within the general scopev of the present invention we; f

have found that the combination of zinc ethylene-bis-dithiocarbamate and calcium pentasuliide is particularly effective. The effectiveness of the composition according to the invention was determined-by testsmon tomato seedlings articiallyinfected with Phytophthora infestans and by tests on small rye plants artificially yinfected with Erysiphe graminis. v

Test procedure: The test plants were sprayed with aqueous 4suspensions or solutions of fungicidal compositions according to the invention and, after drying of. the

spray coating, the plants were artificially infected with the l fungi. The infection'with .Phytophthora infestans .was accomplished by means of a vspore suspension of this fungus which contained 60 to 120,000 sporesqpercubic ene-bis-dithiocarbamate (dotted line a).

The attached drawing represents a graph showing the `individual fungicidal effects of zinc ethylene-bis-dithio- *carbamate and calcium pentasulde, respectively, as a function of their concentration, on the tomato seedlings (inoculated with Phytophthora infestans). The dotted vlines a and b show the concentrations of the two active ingredients which have the same fungicidal effect. These values are summarized in Table 1. The equivalent fungicidal effect for the individual concentrations of the two components is indicated in the last column of Table l.

Table 1.-`-Concentratz'on (in Percent by Weight) of Equal F angicidal Activity of Zinc Ethylene-Bs-Dithiocarbamate and Calcium Pentasuljide in an Inert Carrier Zinc ethyl- Equivalent l Calcium ene-bis- Funglcidal Pentasulde dithiocar- Effect bamate Percent Percent Percent With the aid of the values shown in Table 1 and with the aid of the graphit is possible to express the fungicidal effect of calcium pentasulde in terms of zinc ethylenebis-dithiocarbamate equivalents and vice versa. On the basis ofthese values it is, in turn, possible to determine v values of 0.072 and 0.010 for zinc ethylene-bis-dithiolcarbamate are added. The graph shows that a concentra- V tion of 0.082% by weight zinc ethylene-bis-'dithiocarr-bamate corresponds to an expected fungicidal effect of 90% (broken line I in the graph). However, the actual .fungicidal effect of such .a composition, determined by y' vexperiment, is 99%.

centimeter; the infection with-Erysiphe grantitfzis was accoinplished by means of dry-dusting of the testplants with Erysiphe conidia. The tomato plants were subsequently introduced for 49 hours ,intoa climate chamber with 'steam-saturated air at 20 C.- The area of fungus attack then appeared as, necrotic spots onthe leaves. The fungicidal evaluationwas ,accomplished by estimating the-por- .tiony of the destroyed leaf surface on the total leaf surface which was then compared with the damage done to the leaves of untreated plants. The damage doneto control plants which had not `been ,treated with a fungicidal agent was then given au arbitrary valueof 100. The

incubation period with Erysiphe graminis was 5 to 7 days. ,The fungus developed under a normal green-house climate and .after this period formed white pustules, which were counted on a -leaf section 2 cm. long andwhich were also related to untreated control plants.

The above test'is described in theliterature by P. Schicke, Uber eine .einfache Versuchsanordnung der Fungicidteste mit Phytophthora infestans (Mont.) de

In TableZ the theoretical fungicidal effect of compositions containing various concentrations of zinc ethylenebis-dithiocarbarnate and calcium pentasulde is compared with the fungicidal effect actually found.

Table 2.-Synergistic F ungcidal Effect of a Composition According to the Invention Against Phytophthora infestans on Tomatoes, the Active Ingredient Mixture Containing 25.6% by Weight Zinc Ethylene-Bis-Dithiocarbamate (I) and 74.4% by Weight Calcium Pentasulfide (II) Concentration Percent of Active Fungictdal-Ef- Synerglstie Ingredients in Overfeet in Percent Increase in all Composition liuugicidal Effect.

' Percent I II Additive Actually Expected Found' The vsynergistic increase in fungicidal effect is clear from-thevaluess'hown in the last column of Table 2.

Since rthe synergistic eilect is clearly proven with the aid of the preceding examples, the following tables merely show the synergistic increase in fungicidal eiect `for additional varying quantitative ratios and other dithiocarbamates.

Table 3.-.Syniergistic Increase in Fungicidal Eect of Compositions Containing Mixture of Zinc Ethylene- Bis-Dithiocarbamate (I) and Calcium Pentasulfide (II) at Various Quantitative Ratios (Phytophthora infestf total composition applied, that is including the inert carner.

Particularly useful are the following dithiocarbamates: VZinc ethylene-bis-dithiocarbamate Manganese ethylenc-bis-dithiocarbamate Sodium ethylene-hi's-dithiocarbamate Zinc dimethyl-dithiocarbamate Iron ethylene-bis-dithiocarbamate The compositions according to the invention are emans, Tomatoes) ployed in those forms ,which are customarily used for I. 41.8% I. 25.6% I. 14.9%

II. 58.2% Il. 74.4% II. 85.1%

Concentration Synergistie Concentration synergistic Concentration synergistic ctive Increase in Active Increase in Active Increase in Ingredient Eiect Aboye Ingredient Eiect Above Ingredient Eiect Above Mixture, Theory, Mixture, Theory, Mixture, Theory, percent:l Y percent Percent percent percent percent Table 4.*Synergistic Increase in Fungicidal Eect of Compositions Containing Disodium-Ethylene-Bis-Dithiocarbamate (IV) or Zinc-Dimethyl-Dizhiocarbamate (III) and-'Calcium Pentaswlfide (Il) at Various Quantitative Ratios (Phytophthora infestants, Tomatoes) III. 28.79' IV. 16.37 1I. 11.3%? n. 83.1%?

Concentration `synergistic Concentration synergistic of active increase in oi active increase in ingredient eect above ingredient eiect above mixture, theory, mixture, theory, percent percent percent percent The followingr tableY shows that not only the eiect of the thiocar-bamates against those fungi` onk which theyV a1- ready exhibit a good, eiect is synergistically increased, Ibutv also that the effect of the calcium pentasulidel against true mildew fungi is*synergisticaliyv increased, which is of particular importance in actual practice.

Table 5.-Synergstic Increase in Fungicidal4 Effectiveness of Various Compositions Containinga Mixture'of Calcium Pentasuljde (III) and Zinc Ethylene-Bis-Dithiocarbamate (I) Against Erysiphe graminison RyeY I. 25.517 II. 74.56.'J

synergistic Increase in etect above theory, percent Concentration;

elective ingref -dientmixture,

percent;

fungus control, for example as suspensions, dusting powders or solutions in inert carriers. The following examples will further illustrate the invention, the parts being parts by weight.

(I) Suspension:

67 parts calcium .pentasulde 23 parts zinc, ethylene-bis-dithiocarbamate 7 parts kaolin 3 parts naphthalene; sulfonate 'Ihe individual components are intimately admirred by milling and are then diluted rwith water to the desired concentration of the active fungicidal components.

(2) Solution: 13 parts sodium ethylene-bis-dithiocarbamate, 13 parts calcium pentasuliide and 4 parts naphthalene sulfonate are dissolved in 70 parts water, and the 'resulting solution is diluted to the desired concentration of the active IJu'ngicidal components.

(3).' Dusting powder: 5 parts manganese ethylene-bisdithiocarbamate and, 10 parts calcium pentasulde are thoroughly admixcd with parts kaolin by milling until a homogeneous dusting powder is obtained.

vWhile we have illustrated the present invention with the aid of 'certain speciiic embodiments thereof, it will be readily apparentto those skilled in the art that the invention isnot limited -to these embodiments, and that various changes and: modificationsV may be made without departing from the spirit of the invention or the scope of the appendedy claims.

We claim:

1s. lFungicidalv compositions .comprising from 0.01 to 5% lay-weight of a salt of a dithiocarbamic acid selected from the group consisting of zinc ethylene-bis-dithiocarlbamate, manganese ethylene-bis-dithiocarbamate, sodium ethyleneebis-dithiocarbamate, zinc,y dimethyl-dithiocar- V-bamate and iron ethylene-bis-dithiocarbamate, and from 0:05 to 10% by weight of calcium pentasuliide.

2. Fungicidal compositions comprising from 0.01 to 5%v by weight' of zinc ethylene-bis-dithiocarbamate and 0.05 to 10% by weight of calcium pentasulde.

Y 33.'F111'4g.idall compositions comprising from 0.01 to 5%I by Weight ofzinc dimethyl-dithiocarbamate and from 0.05 to 10% by weight of calcium pentasulde.

4. Fungicidal compositions, comprising from 0.01 to 5% byweight of disodium ethylenesbis-dithiocarbamate and fromOS to 10% =by weight of calcium pentasulide.

References Citedi'n the le of this patent UNITED ST ATES` yPATEISITS lies 23,742..A 1,517,522 

1. FUNGICIDAL COMPOSITIONS COMPRISING FROM 0.01 TO 5% BY WEIGHT OF A SALT OF A DITHIOCARBAMIC ACID SELECTED FROM THE GROUP CONSISTING OF ZINC ETHYLENE-BIS-DITHIOCARBAMATE, MANGANESE ETHYLENE-BIS-DITHIOCARBAMATE, SODIUM ETHYLENE-BIS-DITHIOCARBAMATE, ZINC, DIMETHYL-DITHIOCARBAMATE AND IRON ETHYLENE-BIS-DITHIOCARBAMATE, AND FROM 0.5 TO 10% BY WEIGHT OF CALCIUM PENTASULFIDE. 